From adf9ea89c719c1d23794e363f631e376b3ff8cbc Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Thu, 26 Aug 2021 10:03:15 +0800 Subject: [PATCH] f2fs: fix unexpected ENOENT comes from f2fs_map_blocks() In below path, it will return ENOENT if filesystem is shutdown: - f2fs_map_blocks - f2fs_get_dnode_of_data - f2fs_get_node_page - __get_node_page - read_node_page - is_sbi_flag_set(sbi, SBI_IS_SHUTDOWN) return -ENOENT - force return value from ENOENT to 0 It should be fine for read case, since it indicates a hole condition, and caller could use .m_next_pgofs to skip the hole and continue the lookup. However it may cause confusing for write case, since leaving a hole there, and said nothing was wrong doesn't help. There is at least one case from dax_iomap_actor() will complain that, so fix this in prior to supporting dax in f2fs. xfstest generic/388 reports below warning: ubuntu godown: xfstests-induced forced shutdown of /mnt/scratch_f2fs: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 485833 at fs/dax.c:1127 dax_iomap_actor+0x339/0x370 Call Trace: iomap_apply+0x1c4/0x7b0 ? dax_iomap_rw+0x1c0/0x1c0 dax_iomap_rw+0xad/0x1c0 ? dax_iomap_rw+0x1c0/0x1c0 f2fs_file_write_iter+0x5ab/0x970 [f2fs] do_iter_readv_writev+0x273/0x2e0 do_iter_write+0xab/0x1f0 vfs_iter_write+0x21/0x40 iter_file_splice_write+0x287/0x540 do_splice+0x37c/0xa60 __x64_sys_splice+0x15f/0x3a0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae ubuntu godown: xfstests-induced forced shutdown of /mnt/scratch_f2fs: ------------[ cut here ]------------ RIP: 0010:dax_iomap_pte_fault.isra.0+0x72e/0x14a0 Call Trace: dax_iomap_fault+0x44/0x70 f2fs_dax_huge_fault+0x155/0x400 [f2fs] f2fs_dax_fault+0x18/0x30 [f2fs] __do_fault+0x4e/0x120 do_fault+0x3cf/0x7a0 __handle_mm_fault+0xa8c/0xf20 ? find_held_lock+0x39/0xd0 handle_mm_fault+0x1b6/0x480 do_user_addr_fault+0x320/0xcd0 ? rcu_read_lock_sched_held+0x67/0xc0 exc_page_fault+0x77/0x3f0 ? asm_exc_page_fault+0x8/0x30 asm_exc_page_fault+0x1e/0x30 Fixes: 83a3bfdb5a8a ("f2fs: indicate shutdown f2fs to allow unmount successfully") Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/data.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 5e4120b92f59..8e8824605f83 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1504,7 +1504,21 @@ next_dnode: if (err) { if (flag == F2FS_GET_BLOCK_BMAP) map->m_pblk = 0; + if (err == -ENOENT) { + /* + * There is one exceptional case that read_node_page() + * may return -ENOENT due to filesystem has been + * shutdown or cp_error, so force to convert error + * number to EIO for such case. + */ + if (map->m_may_create && + (is_sbi_flag_set(sbi, SBI_IS_SHUTDOWN) || + f2fs_cp_error(sbi))) { + err = -EIO; + goto unlock_out; + } + err = 0; if (map->m_next_pgofs) *map->m_next_pgofs =